Fused filament fabrication (FFF), also referred to in the art as thermoplastic extrusion, plastic jet printing (PJP), fused filament method (FFM), or fusion deposition modeling, is an additive manufacturing process wherein a material is extruded in successive layers onto a platform to form a 3-dimensional product. Typically, FFF uses a melted thermoplastic material that is extruded onto a lower-temperature platform. Three-dimensional printing (3D printing) often uses support structures which are easily dissolved or removed from the part after it is finished.
Disadvantages of existing FFF technology using thermoplastics include single material property printing, limited print-direction strength, limited durability, and limited softness. Thermosetting materials have generally not been used in FFF because prior to cure, the monomers are low viscosity liquids, and upon deposition, the curing liquid flows or breaks into droplets, resulting in finished parts of low quality and undesirably low resolution. In practice, attempts to print with thermoset materials has required addition of fillers (such as inorganic powders or polymers) to induce thixotropic behavior in the resin before it is fully cured. These solutions affect the final properties of the printed part. Other problems include poor resolution control in the printed part and frequent clogging of mixing systems.